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Sunday, 10 March 2013

IS-2 vs. the German Big Cats

I have written a great deal about the D-25's accuracy (combat and test) and penetration, but what happens when you combine the two, and have some captured Tigers and Panthers laying around? Let's find out!

2. Penetration. Breach 130 mm by 230 mm. Turret torn off the turret ring and displaced to the rear by 500 mm.

Distance: 1400 m.

Photo #34. Turret fragment torn off my penetration #1."

Now, for the Tiger.

CAMD RF 38-11377-12

These tests use the "Corps level 122 mm gun model 1931", more commonly known as the A-19, the precursor to the D-25. With the BR-471 shell, shooting at 1500 meters, the following was observed:

"Shot #1. The shell passed through a previously made opening in the front armour, went through the tank, and penetrated the rear. The entrance hole is 140 mm in diameter. The exit hole is 225 mm in diameter. Three cracks formed at the penetration point, 240 mm, 300 mm, and 220 mm in length. Three bolts holding armour screens were torn off.

Shot #2. The shell tore off a piece of armour off the turret 580 mm by 230 mm. The turret was torn off its turret ring, and displaced backwards by 540 mm.

With this Tiger, you can see the armour crack as it is hit. This is really bad, since cracking armour is indicative of the plates being too brittle. While brittle plates are more likely to shatter a kinetic penetrator, they are also likely to shatter themselves, sending armour fragments into the crew and the tank's internal components.

Now, let's take a look at the Tiger II. This report is much more detailed than the previous ones, so I won't be posting pictures. However, you can grab the report here, courtesy of litl-bro. Also, here's the picture of the Tiger II after the penetration trials, which adequately communicates what happened.

"Shot #1. Target: upper front plate. Shell: 122 mm HE-fragmentation.

Result: spalling across an area 300 mm by 300 mm. The welding seam between the upper front plate and the machine gun port burst on 3/4 of its circumference. Internal bolts holding the machine gun ball were torn off. The welding seam between the upper front plate and the right side burst, and the right side was displaced by 5 mm. The tank caught fire internally."

Here are those German welding seams, causing trouble again. If an enemy shell literally tears your tank apart without even penetrating it, that's bad news for you. The spalling and machine gun bolts flying around mean that the driver and radio operator would be dead. Let's read on.

Result: dent 310 mm by 300 mm, 100 mm deep. On the rear side, a piece of armour 160 mm by 170 mm and 50 mm deep cracked off. The welding seam between the upper front plate and hull roof burst. All seams between the upper and lower front plates burst. The seam between the lower left hull and the left side of the hull burst. The driver's observation device was torn off."

Here, we see the perils of overly hard armour again. Even though the shell did not penetrate, the large chunk of armour that flew off the other end effectively carried out the shell's job, killing crew members and destroying tank components. The driver now has his observation device embedded in his skull, which doesn't increase his effectiveness any. More welding seams fail throughout the tank.

Result: penetration, hole is 180 mm by 250 mm. A piece of armour is torn off the rear side, 580 mm by 500 mm, 80 mm in thickness. The shell struck close to the non-penetrating hit from shell #3. The shell remained in the tank."

This is some pretty massive damage. The piece of armour that fell off further indicates the rapidly decreasing quality of German armour as the war went on.

Ironically, the effects of the 122 mm gun on the lower front plate were not as effective. However, shots to the upper front plate from any reasonable distance harmed the tank greatly. Let's see what happens when you shoot at the turret.

Result: A piece 700 mm by 220 mm was torn off the turret front. The shell penetrated completely. The roof of the turret is missing a piece 460 mm by 300 mm. The rear of the turret has two cracks through its entire thickness, through the welding seam of the roof and left turret side, 1100 mm in length, and on the turret roof, 1350 mm in length."

For a change of pace, this time the turret didn't fall off. However, it might as well have. It's missing massive chunks of armour, and is cracked significantly. Another demonstration of overly brittle armour.

Result: a dent 200 mm by 230 mm, 90 mm deep. The rear side of the armour had a bump with cracks. The welding seam between the turret front and the bracing strut has a 200 mm crack."

Again, shooting at ridiculous distances using a reduced propellant charge doesn't do you any good. However, it has been demonstrated that the IS-2 can take out a Tiger II at over 2500 m by penetrating the turret, and does not even have to penetrate the upper glacis plate to incapacitate the tank and its crew.

Regarding ridiculous distances and reduced propellant: they simply simulate distance by varying propellant amount so shell velocity is the same as if the shell actually flew all that distance. Same with "direct hit at cupola @ 800m" by the way. IRL the gun was fixed 50-100 meters away from target. This is common practice for penetration tests (at least here in Russia) so you should read "xxxx meters, reduced propellant" as "propellant amount was reduced to simulate xxxx meters distance".

35 shots on the T2!!! For objectivity, you'd need to see the effect of 35 kwk-43 shots on an IS2. I suggest it would look even worse. But none of this changes the reality of what happened in combat during the war. It's really just a pointless exercise.

Flat-nose 122mm APBC (BR-471B) was not in production during WWII. It was ordered, and developed, and tested, but not used by front line troops. Or so I have read. Pointed-nose AP was used in combat(BR-471). Judging by the effects shown in this article, the German armor would collapse under attack by either projectile type, so the difference is academic. The USA conducted penetration tests of BR-471B after WWII, against US test plate, as the 122 was a much-feared weapon during the early Cold War.

And like all other 'test' vehicles had the gun, mantlet, tracks and engine removed. Then peppered with dozens of medium and large calibre rounds. Finally the Soviet would fire a round with the gun they were 'testing' and we're supposed to be amazed that it managed to penetrate/damage a shot up wreck?

The photo's are interesting for sure, but no one should try to derive any conclusions from these 'tests'. As mentioned, hammer an IS-2 (wreck) with 7.5 cm and 8.8 cm rounds from Panthers, Tigers and Tiger II's and you will get the same (meaningless) results.

It's not "meaningless" if performed properly, if you're referring to armor fatigue. I would think that part of any reasonable testing protocol would be to start with the least potent weapons at long range, closing until either a "penetration" or "no penetration" result at very close range was obtained. Then you up the ante with increasingly more potent weaponry and save the most potent weapons for last.

its a pointless test every tank would ended like this after so many shots but in real war most russian tanks shot few ..one two times(mostly missed first time) and then got an kind reply and that was it for them. if they had let the german tanks shot back there would be no IS-2 anymore especially with the Kingtiger lol what an joke test so far from real conditions...

Is2 pen KT at 2500m is just a soviet wet dream that lives even today same as rest of allies says today their sherman could kill tigers,panther,KT's etc frontally at 1+km even if Gen.Eisenhower confirmed that even "upgraded"shermans aka easy 8 had to come less then 200 yards to frontally kill tigers.....plus as some1 already posted above "Flat-nose 122mm APBC (BR-471B)was not produced in WW2" meaning this test happend after WW2(could be a months after or a decade) but ruskies just cant deal with the facts just like rest of allies that germans had better tanks(even if they were overengineered peice of crap as they call it)& especially better AT guns & still do even today(dont believe me well just check whose guns most countries uses on their tanks today.....a hint......name starts with R).

These tests aren't 'meaningless' as some of you say. Granted multiple shot on ANY type of armor are eventually going to weaken it and the result is a tank ripped to pieces. Even Chobham armor will fail eventually. It was pointed out that the FIRST HE round fired at the Tiger 2's glacis did catastrophic damage to the interior of the tank. Nuff said.

Do you think really a tank named the "stalin" would have a faire comparison by the russian themself ? What a joke. This is pure propaganda. just lock for picture for damaged tiger or/and panther. Even when destroyed (penetrated), you will see many, many dent of unprenetring shots. Please try to find picture of T34 or is2 with similar dents ... there are not. Every hits for these tanks was fatal. Large casted pieces, especially at russian factory, were full of default, compared to rolled homegenous armour, like the one used for the german tanks.

lolthe germans reallllly feared the hand loading is tanks and how the sovjet troops were know for sometimes dropping the shell inside the tank while trying to load and once they had loaded the germans know the sovjets were gonna miss

sovjets only advantage against germany were their numbers

send enough cheap and finally the bullets will run out and when you no longer have the strength to kill them with your bare hands they roll over you

Er, much the opposite. Do you think the russians would *dare* fudge test results on a tank that was going to be named after the Boss himself? Knowing that if the tank was found to underperform in combat, it's going to come back to them?

Reminder that the designers who fucked up with the SU-76 were sent straight to the front lines, where they were killed. No one is going to deceive in soviet internal documents.

We already know the answer, the IS-2 could in fact receive multiple hits from a 88/L71 on the King Tiger at ranges over 1500 m and survive (that's not test results, but the report from a King Tiger crew who bounced seven hits off an IS-2 before it was finally destroyed at 700 m.

Reaserds more familar with the test may notice that the article omits the projectiles, which failed to penetrate. It also doesn´t factor in plate edge effects and weakened structures by previous impacts within 2 cal distance.

Yes an interestingly enough it was claimed that with the "B" round penetration of 80-85mm plates at 55 deg only transpired at 1800 meters with this round and with the standard BR-471 AP shot no penetration could be made. I don't recall what other plates were tested but its interesting these effects were observed as they match up with Wapruf tabulations and also if you calculate armor deficiency the numbers you get tabulate with the Kurbinka tests 2000+ meter pen with B round and the familiar number of 700meters with AP.

it's obvious that the last image of the destroyed tank, doesn't have much relation with the power of the cannon, when the pierce take damage in the engine or munition, it's only a secondary instance, the pierce makes a hole, but the thing that we see in the photos, it's the effect of the explosion of fuel, or munition, mostly produced, a few minutes after the main impact.

Mostly times, but we are not discussing that, because its maybe though that a 122 impact can blow a 30 ton turret, but as i say, its the fuel, or ammunition explosion, that are seen in the photos , what we see in the reports. The impact is a hole, the effect, could be total destruction, it all depends of were it take place.

Whatever anyone thinks of the testing, the fact is that no less of an authority than Hasso von Manteufel said the IS-2 was the best tank of the war. Hard to argue much with the opinion of the guy who had to deal with them.

"The Stalin tank is the heaviest in the world; it has robust tracks and good armour. A further advantage is its low build - it is 51 cm lower than our Panzer V, the Panther. As a 'breakthrough' tank it is undoubtedly good, but too slow."... ..."Fire-power, armour protection, speed and cross-country performance are the essentials, and the best type of tank is that which combines these conflicting requirements with most success. In my opinion the German Panzer V, the 'Panther', was the most satisfactory of all, and would have been dose to the ideal had it been possible to design with a lower silhouette"-Hasso von ManteufelI would read that as: "IS is really good, but too slow" ..."Panther is the best, not perfect, but the best available "

It seems Hasso forgot the context, the Panther was good from German prespective because their doctrine was defensive when this kitty was fielded, from offensive prespective this was a bad tank. It's sides were vulnerable even to antitank rifles, taking this in account I would say the Panther was not a tank but a tank hunter.

If you look carefully at the Tiger-II's turret pictured here in the 12cm D-25 ballistic tests and compare that to the turret penetrations of the 8.8cm Pak43 L/71 tests, you can see that the same tank was used in both tests.

I am currently under the impression that the gun is placed directly in front of the tank. however am i to understand that this is how it will be in combat conditions? I hear very many things did not happen the way they were supposed to

A lot of soviet bullshit!!!They could not penetrate tiger2 front armour at normal combat range!!!Not even panther glacis,except closer than 600 meters!Their tests are pure propaganda!They had to use assault guns against Tiger2,SU-100,SU152!Read about the Budapest battle,they urgently sent SU-100 guns to the front to counter german offensive!Why,if IS-2 was so effective???

Many people say that IS 2 was breakthrought tank, but in fact it was the best russian tank destroyer too, in frontal combat. It was the best armoured russian vehicle, no russian tank or SPG couldnt destroy enemy tanks and SPG from bigger distance than IS 2. And the most important thing is that it is tank, it has turret.

Yes you are right 122 mm couldnt penetrate panther front glacis from more than 600m. Why? Because A19 guns never werent normaly used in antitank role before. Their AP shells were just fuse in case they should meet enemy tanks, and were poor quality. Also SU 152 got AP shell for this case, and they were poor quality because you can read in the article SU/ISU-152 vs the German Big Cats that when fired from 100 m it didnt copletely penetrate Tiger II armour, because half of shell got stuck in the lower plate.After they improved quality of D25 shell and German tanks armour quality was decreased cause lack of some elements the ability of russian gun to penetrate german tan rapidly increased:http://bronetehnika.narod.ru/is2/is2_3.htmlLook at that hole in panthers hull front. Its bigger than caliber.And if Pak 43 was effective against Tiger II hull front, why does D25 couldnt? Seriously, what is stroger for you? Is it 10 kg shell flying at 1000 m/s or 25 kg shell flying by 800 m/s?

I made a mistake, it's not the same plate on #33 and #34.On #33 is Panther D left side plate which is still in place, (please correct me if I'm wrong).

On #34 is cleanly removed or torn off right side plate with different shot hole pattern.

All the holes seems to be inward. But I could be mistaken, the snapshosts are not clear enough for me.

The edges of the removed plate are very clean. Normally the welds breaks not so cleanly.Also the edges on the turret are very clean and there are patches of light color like some grinder was used.

Strange thing is that the place of impact on #33 seems to be identical to where the small rounded port is. It seems like the shot impacted directly at the port plug (weakest place on side of the Panther D turret)

Another thing is I don't see any turret displacement.The turret seems to be exactly as where it should be from this angle.Definitelly not 50 cm displacement, but I could be wrong.

It's worth to note, that this test of 122mm against KT was done using A-19 gun, not it's D-25T tank version. . And according to some ballistic tables the A-19 had somewhat greater muzzle velocity (over 800m/s) giving it about 160-300m advantage over D-25T (781m/s) gun in performance (penetration distances).

So substract about 170m from every result of 122mm ammo (BR-471) fired from A-19 in this test, to get D-25 performance with the same shell. (Would be 300m of difference for BR-471B).

Don't be oversensitive, Peter. I didn't say it disproves anything. Just noticed, for historical correctness, that A-19 != D-25T and there is a slight difference, that is worth about 150m of range. 150m of difference is not big, but still may be important for some. That's all.

In a different post, you mentioned that some people dismiss some things as propaganda, such as a table of penetration tables. Well, if you want to give the appearance of not being biased, you should probably take off all the Soviet war medals in the background. Like the one for "Victory over Germany in the Great Patriotic War". This website isn't about Soviet war medals so when someone sees that, they immediately start to think (before they have read even one word) that the website information will be biased. It is obvious that your personal bias is towards the Soviets, I'm not necessarily saying that this bias has crept into your articles, but having this imagery weakens your arguments.

The tests proves that German armro quality degraded greatly by late war. Early war German armro were very malleable and hard. So while it coudld resist shells well it didn't spall much. In fact they complained the Czech tanks as brittle.FHA does naturally spalled more but German armor were very good. They were the leading country in armro technology of the time. As evidence, most warships used Krupp cemented armor. For instance. And other types of armro were shown to be high quality. At least for naval vessels. This translate the same for tanks. But as materials became scarce, they could not keep up the quality.

Another reason why upper hull was weaker is due to the machine gun and hatches. bolts, and attachments on a armro plate creates weakness. Thats why shooting lower will not penetrate while shooting higher will. Machine holes on the upper hull meant less structural integrity. Same with turret face, though based on description, it sounds more like massive spalling from poor armor quality.

If the Tiger Ii had early war armor quality, I doubt the IS-2 could of penetrated it unless at close ranges

People are dunce. Tanks would take multiple hits. Nice to see that at 1500 yards their armour was compromised. With that piece of info, a second round would have destroyed the tank if not the first round. A fracture in armour isn't a good thing.